The present invention generally relates to a circuit arrangement for generating a resistance behavior with an adjustable positive temperature coefficient as well as the application of this circuit arrangement in a current mirror circuit.
A temperature compensation circuit with a fixed compensation behavior is known, for example, from Tietze/Schenk, Halbletier-Schaltungstechnik, Springer-Verlag, 7.sup.th ed., Chapter 4.6.3. As provided in this teaching, a diode is connected in the input current path of a simple current mirror. The diode compensates the temperature effect in the transistor in the output current path. However, the compensation is fixed by the selection of the diode.
A large number of electrical and electronic components, such as, for example, light-emitting diodes, laser diodes, sensors, display elements, controllers, etc., provide during operation an undesired temperature dependency with a negative coefficient. In order to achieve a constant behavior over a large temperature region, corrective circuits with positive temperature coefficients are often provided in components of this sort. Since these temperature coefficients are supposed to assume different values according to the component to be compensated, different compensation circuits or compensation elements must be used, depending on the respective component. An adaptation to the temperature behavior of the respective component is, therefore, typically expensive to construct.